Centrifugal scrubber



May 2o,l 1930.

P. M. KUEHN GENTRIFUGAL SGRUBBER v Filed may 31, 1927 3 Sheets-Sheet Mayzo, 1930. P M, KUEHN 1,759,315

CENTRIFUGAL SCRUBBER Filed May 31, 1927 5 Sheets-Sheet 2 n* fall] .M1,16%??? Ey @www Patented May `20, .1930 Y UNITED STATES PATENT 'OFFICEPAUL M. KUEHN, -OIE' BALTIMORE, MARYLAND, ASSIGNOR TO THE BARTLE-TT HAY-WARD COMPANY, OF BALTIMORE, MARYLAND, A CORPORATION OF MARYLANDCENTRIEUGAL SGRUBBER Application filed May 31, 1927.l Serial No.195,557.

This invention pertains to that type of liquid and gasv contactapparatus commonly known in the art as centrifugal scrubbers.

Such scrubbers have longy been in use and probably the best known andmost successful form is that commonly designated as the Feld scrubbershown generally in U. S. Letters Patent to Walther Feld Nos. 829,261,VV940,103 and 983,037. j

The structure lof the present invention is of the same centrifugal LtypebutV is so constructed and arranged*l as to produce more eiiicientresultsy and this with the expenditureof less power or energy to actuatethe same.

Aside from the advantage just expressed thel invention has for itsfurther object the production of a pumping element which will ,eectivelyelevate the liquid from the pan below .saidl element and initially sprayor break up the liquid as it is thrown outwardly by centrifugal actionprior to its passage through a screen surface, rotatable with thepumping element, by which screen the liquid is brought to the iinaliorultimate degree of neness at which time itis in counter-flow contactwith the gas. i A further object of the invention is to provide thepumping element with special buckets, scoops orblades at the lower 'endthereof which members gather the liquid from the underlying pan andstart the same upwardly ,along the innerface of the pumping element thusassisting, to a greater or less degree, the centrifugal action of theelement in elevating the liquid.

A still further object of the invention is to provide a pan of specialformation as to the gas passages which extend therethrough and in sodoing to produce channels yor ways which effectively return the sprayedliquid to the center of the pan or to the zone of operas tion of thebuckets or scoops carried at the lower end of the pumping element-andthis without any undue restriction of the gas flow which would lead to back pressure.

With these and other objects and advantages as will hereinafter appear,reference is had toy the annexed drawings illustrative of yoneembodiment of the invention, wherein;

'line III-III of Figure 2;

Figurel is a vertical sectional elevation of the scrubber;

Figure 2 a similar view of one of the pumping elements and itscooperating screen or spray forming element;

Figure 3 a transverse horizontal section View of the pumping elementtaken on the Figure 4 a sectional plan view showing one ofthe liquidgathering pans or receptacles, t

the section being on the line lV-IV of Figure 1; and n Figure 5 a sideelevation thereof with parts broken away and shown in section. y v

In said drawings 1 denotes the shell or c as'- ing which in practicewill be preferably made up from a series of sections asis usual in theart and secured together in any approvedV manner.

The number of sections and consequently the height of the shell willofcourse be dependent upon the desired capacity o f the machine rand whilethree pumping ele-v ments are shown in Figure 1 it is to be understoodthat a greater or 'less number may be employed.

At itslower end thecasing is provided with a gas inlet'2 and a draw-off3 while at the upper portion a gas outlet or olf-take 4 is provided, themouth of the latter being shielded from direct communication with` thespray chamber next adjacent by an inwardly extending shield or'bafleplate 5. i i

Extending through the shell or casing is a vertically disposed shaft 6supportedat its upper end by any suitable form of bearing designated by7 and designed to be driven by suitable means as an electric motor y8.The lower end of the shaft extends into a bearing 9 which holds theshaft from lateral deflection.

i The shellris divided into what `may ber termed a series of chambersproduced by spaced pans, hereinafter specically de.- scribed, extendingtransversely of the shell or casing. Said chambers are designatedgenerally by the reference numerals 10, 11, 12 and 13. v Y

Inasmuch as the various pans and pumping spraying elements are alikethroughoutthefsrubber, a description ef @ne set of 'such elements willsuffice. VIn the instant case three pans are shown, they beingdesignated generally by 14, 14a' and 141" They aregof Aa diametersubstantially equal to thatof the interior of the shell and supportedfrom' the wall thereof bybrackets 15.

. YThe bottom 16 of the pan is provided'with a centrally disposedopening through which the shaft 6V extends and an upstanding collar 17,Y*spaced awayfromfthe shaft is provided at .this point. `The rim y18'iscontinuous and a weir plate 19 vis a-djustably secured thereto Y so thatth-e depth of liquid in the VVpan Vmay,

be regulated and determined. Y

vFormed inthe bottom V16 of the panis a vseries of symmetricallydisposed openings 20 generally segmentalin outline' and defined byYwalls extending upwardly fromthe bottom. The innermost wall 'is'designated by 21, the

outer end whereof is in'contact with and secured to the'rim18 of thepan. From this Ypoint it extends inwardly in a curve towardV the centerof the-pan to apoint 22 Where vrit is recurved producing a wallsection-23 `which is substantially concentric with the Center or axis'ofthe pan. Y

4VThe Vouter wall is designatediby24 and is preferably formed upon anunbrokenrcurved line. Y At itsT outer end it is connected tothe wallsection 21 at a. pointspaced inwardV of lthe rim* 18 and from that pointvgradually Vcurves inward Vaway from the rim.V There is thus formedbetween such wallv 24 and rimy 18 a passage-way or channel of graduallyincreasing width from the outerportion to the innerend where the channeldischarges into fwhatfmay be termed a centralr chamber or gatheringchamber defined by the upstanding concentric wall sections 23. Thus itwill ,be seen that there is formed upon the base or j bottom 16. of thepan,VV an series of channels designated generally by 25 formed by therim 18, the walls24, and thesections 21 of the inner walls and that saidchannels discharge the liquid onto-the L"central portion of the panor'intothe centralgathering space. As will be seen v'upon referencetoFigures 1 and 5, the

`walls 21 and 24 will preferably be made high- L. ering member ordeflector 26, the Vlower inner edge whereof overlies and extendsdownwardly into the pan.V Said member serves to return the sprayedliquid back to the pan and likewise prevents the gas from passing-dhrectly in an upward direction through the spaces between the outeredges-of the pan and the wall ofthe apparatus.

.Y The pumping and spray producing elements nor means are best shown inigures 2 and 3 and as they arealike in construction eter toward theupper end thereof;

a description of one will sufiice,H it being understoodthat there isoneof such elements disposed in each chamber other than 10, in

operative vrelation tothe liquid` vwithin 'the underlying pan. Y

spraying element comprises aninverted frusto-.conical member 27 andwhile the same is shown of a trulyfrusto-conicalV form the wall thereofmay be curved. Y -1 Y Y Said bodyhas secured tothe upper'end orportionthereof, by electric-welding orotherwise,ak horizontally`disposed ring shaped member 28to which is attached a spider,.- frame'29having a hub 30. The frame isVV `secured to shaft 6 for rot-ationtherewith' by y lany Vsuitable means as by Vwedge blocks 31 formed toengage the sha-ftand a pin carried thereby, as in Figure 2. 'This is ofusual construction. g

Body element 27 is'provided with a'series ofopenings 32 throughout itsupper portion,

said openings as shown, increasing indiam- At its lower open endthepumping elementl.

or member 27;,will -be'provided with aseries Y of scoops or bucketswhich extend down into ,the liquid in the central or gathering portionVof the pan.l As illustrated,y these scoops 4or buckets are each'producedfrom sheetmetah or plate 33 bent to form and secured at theirV advancingedges 34, as by welding, to the inner `face of the member (27 into whichthe scoop may be said to merge.

, As will be best seen upon reference to Figure 2, the advancing edge34of each scoop stands at an angle Vtothe axis of shaft 6 or;

in other words, inclines rearwardly with `reference to the lower edge ofthe body 27, this assuming that the element 27 'rotates clockwise asindicated bythe arrow inFigure 3.

. The lower end of each plate is bent inwardly at right angles, as -at35 forminga ,wallor flange jwhich is `inclined upwardly and rearwardlyat substantially rightangles to the advancing edge `34 and inasmuch asvv the plates or bodies 33 are curved transversely the vflange vanishesas it reaches thev trailing inclined edge 36 of the plate.V Y Y As willbe seenupon reference to Figure2',

the'major portiongof each plate extends below the lower edge'vof thebody 27, theflanges or walls 35 being entirely sowhile thefmajorportions of th-eadvancing edges 34 are like,-

wise positioned. I

To maintain the overlapped and spacedl bucket or scoop elements inposition there isV `preferably employedV a tie plate or memberV Y 37 offrusto-co-nical form which is welded to `12.5 the upperedges of theflanges 35. Said mem ber 37, in addition to tying'the parts togetherVand maintaining the buckets intheir .proper spacedV relation, likewiseassists in ,securingr an even and 'distributed flow of the The main bodyof the pumping and initialV '70 i i soY 7 up along the surface of thepumping and distributing element 27. Y

Secured to the upper end ofsaid element 27 and surrounding the same inspaced relation i thereto is an annular screen 38 having a multi- ,ff 27in any suitable manner, as by inwardly extending flanges 40 and 41,welded or otherwise secured tosaid member.

Liquid will be supplied to the various pans in any suitable manner asthrough a main 42, Figure 1, having valved branches 43 opening into thevarious chambers.

To prevent the gas which is forced into chamber 10 from passing upwardlyabout shaft 6 a casing 44 extending upwardly from the bottom of theapparatus to the pan 14 surrounds the shaft at this point. A cap piece45 carried by shaft 6 overlies the upper end of the flange or collar 17of the pan 14 and thus flow of gas upwardly about the shaft is cut offat this point.

It is thought that the operation. of the apparatus will be apparent fromthe foregoing description but a brief resum will be Given. Assuming thatthe pans are filled a ibvith liquid and the laterals closed and gas isforced inwardly through the opening 2 and the shaft 6 is being rotated.Under these conditions the liquid would be picked up from each of thepans by the scoops or blades at the lower end of the frusto-conicalpumping element, carried up along the inner face thereof outwardlythrough the openings 32 and through the openings 39 in the screensurface 38.

.Centrifugal action causes the liquid to travel upwardly along the innerface of the member 27, through the openings 32, and

through the openings 39. As it passes from the openings 39 it will be inthe form of a fine rain or spray which is thrown outwardly toward theinner wall of the shell or casing 1 with which it contacts, running downsaid face, passes o-ver the deector or gatherer plate 26 and is returnedto the pan. It then g' flows toward the center. of the pan through thepassages or channels 25 and again comes in the path of the scoops korblades by which it is again lifted and carried through the same cycle asjust outlined.

At the same time the gas which is forced inwardly under pressure willpass through the openings 20 in the various pans and in passing from oneset o-r series'of openings to another the gas will of necessity have topass through the outwardly thrown rain or spray of liquid where intimateand close contact between the sub-divided liquid and the gas parvticlesis effected.

The fineness of the spray may be readily determined by changing the sizeofthe openings 32 and the openings 39 also to a greater orless extent byvarying the speed ofrotation'by the pumping elements and the associatedscreens.

It will also be noted that the gas in the present apparatus does notpassthrough the screens but merely passes through the spray outward ofthe screens orbetween the screens and the wall of the casing. Thus thescreens Vare not so likely tobecome clogged las would be the case wherethe gas passes through thev screen surface along with the liquid.

Y Any gas which may pass upwardlybetween the outer portions of the pansand the inner face of therwall of the scrubber will of necessity beforced vbeneath the lower edge of the gathering element 26 and throughthe liquid in the pan, if in fact any gas passes at all beliieath thelower edge ofsaid gathering memer. j 'Y y u, Y' i It will, of course,beunderstoodthat the scrubber may be employed for various purposes andthat it may be used for recirculation .o-f the sprayed .liquid by merelyclosing the laterals 43 after the pans have been filled,

as above noted, or by leaving the upper 'lateral liquid andfupcominggas.. Y,

While Il have described the buckets or scoops as being made of sheetsteel, it will be open-secure a continuous; counter-flow of theappreciated, of course, that any suitable metal maybe employed and thatthe elements may be secured in place by riveting; or vthe like. So too,inthe broader aspect of the invention, it Vis possible that the bucketsmay. be. formed integrally with the body of the Vmember 27.

The uses to which the apparatus may be put are manifold but for the sakeof brevity the term scrubber will be employed in the claims ,-.the useof such term, Y however, is nototo be taken in any sense as alimitation.; What is 'claimed is: i i i 1. Ina centrifugal scrubber, thecombination of la casing; a pumping member mounted therein, said membercomprising a body kelement of inverted substantially frusto-.conical .1;

form; a lseries of overlapping" and spaced plates secured at their upperends to theinner face of the lower portion of the body element, each,Aof Y said platesl atV its lower end being formed with an inturnedsection, said section 1fmounted therein, said receptacle having aVseries of openings extending upwardly therethrough; walls extending fromthe bottomTSO f f V Y 1,759,315

`of the pan-like receptacle about each ofsaid A fopenings, the outerportion ofsaid walls ex# tending to the wall of the casing-therebyforming channels .for Athe return of liquid toV Y `the center of thepan;a shaft;V a pumping element secured `tothe shaft and rotatabletherewith, the: lower 'Vend of thek pumping element extending into thecentral portion of `the pan; and meansfassociated with saidpumping'element for 'spraying the liquid 'ele-LV vated by the pumpingelement Voutwardly `against the wall vof the shell or casing. 3. In acentrifugal scrubber, the combina,-

tion of a shell or'casing'; a pan-likek recepf tacleV extendingtransversely thereof, said pan having a series of lsymmetricallydisposed openings formed in the bot-tomV thereof, said openings beingbounded by upstanding walls arranged about each opening with'at leastone wall extending to the wall of the shell thereby "forming aplurality` of "channels extending VYinwardly from-the outer portion lofthe panY to the centralA portion thereof; a shaft, a Y' pumping elementsecured toV and rotatable Y n gradually extends inwardly toward thecentral portion of the pan while the inner wall Y of each of saidopenings is formed upon a broken curve'dline, the inner portion of whichlislsubstantiallyV concentric with theaxis of the pan whereby a seriesof channels is formed vbetween the outer wall of the pan and the wallsof the openings, which channelscurve inwardly and discharge into thecentral portion of the pan; a shaft; a pumping velement i securedthereto, the lower end whereof extends into the central portion of thepan;

means associated with the upper end ofthe pumping element forvsprayingthe liquid raised thereby and means for returning the sprayed liquid tothe pan.

-In testimony whereof IV have signed'my name to this specification. l Y

- Y f PAUL M,VKUEHN.`

.msV

